Measured-service telephone system



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APPLICATION FILED DEC- 8. |906.

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EDWARD D. FALES, OF CHICAGO, IIiLINOIS, ASSIGNOR, BY MESNE ASSIGNMENTS, TO FIRST TRUST AND SAVINGS BANK, TRUSTEE, OF CHICAGO, ILLINOIS.

MEASURED-SERVICE TELEPHONE SYSTEM.

Specification of Letters Patent.

Patented Aug. i, raie.

To all whom t may concern.'

Be itknown thatI, EDWARD D. FALns, a citizen of the United States of America, and resident of Chicago, Cook county, Illinois, have invented a certain new and useful Improvement in Measured-Service Telephone Systems, of which the following is a speciiication.

My invention relates to telephone exchange systems in general, and more particularly .to common battery automatic telephone exchange systems in which provisions are made for measuring the service, as, for example by means of call-registering devices located at the exchange or central station.

Generally stated the object of my invention is the provision of a measured-service automatic telephone exchange system of an improved and highly efficient character.

Special objects are the provision of an improved call-registeringidevice or meter which is responsive to the called subscriber, and which is operated by the latter when he takes down his receiver to answer the call.; the provision of an improved call-registering device or meter which is operated by current supplied from the common battery or centralized source of talking current; and the provision of certain details and features of improvement and combinations tending to increase the general etliciency of a measured-service telephone exchange system of this particular character.

To the foregoing and 'other' useful ends,

my invention consists in matters hereinafter' set forth and claimed.

In the accompanying drawings, Figure 1 shows diagrammatically an established connection between a calling line and a called line in a measured-service automatic tele-f States Patent No. 815,321, granted Marchy 13, 1906, to Keith, Erickson, and Erickson, and connector switches, the general mechanical operations of which latter are similar to design `shown at F.

those of the connector switches disclosed in United States Patent No. 815,176, granted March 13, 1906, to Keith, Erickson, and Erickson, but the circuits of which are moditied for common battery work.

The calling substation is shown at A and the called substation at A. The said substations are connected at the central ofiice (through the switches allotted to each) with a central battery Bwhich supplies the system with all necessary current for talking and switching purposes. The selector allotted to the calling line is shown at C; the selector allotted to the called line is shown at C; and the connector switch is shown at D. In the exchange there is also provided a ringer generator E for supplying ringing current, and there is also busy current supplying apparatus of any suitable As shown,` the said device comprises an interrupter, one terminal of which is grounded and thus put in connection with the grounded terminal G- of battery B. The meter for registering calls is shown at I-I and the magnets and circuits whereby the meter is successfully operated will be fully disclosed. The said meter, as shown, is attached to the selector switch C, without modifying any of the circuits thereof as disclosed in the said patent.

The substation A is provided with any suitable dial of the ordinary type, which is not shown but which, it will be understood, is secured to the shaft 2. The substation is, furthermore, provided with means for sending impulses to the line conductors- 3 and 4. The impulsetransmittingdevice comprises an' impulse wheel 5 that is equipped with so called vertical impulse teeth G and with arotary impulse tooth 7 The former, namely the vertical impulse teeth 6, are adapted to engage an impulsetransmitting spring S known as the vertical impulse spring, while the rotary impulse tooth 7 is adapted to operate a corresponding and so-.called rotary impulse spring 9, whereby the said impulse springs 8 and 9 are, in a proper manner, pressed into engagement with the so-called ground post 10, whereby ground impulses are transmitted to the line conductors 3 and 4. This ground post 10 is, of course, connected with the substation' ground GrV while the mechanism is being operated for calling. The switch-hook l1 is, of course, made to control the substation circuits in a manner that is customary. For example, through the medium of the switch-hook the transmitter, which isshown at 12, together with the primary winding 13 of the induction-coil 14 are disconnected. from across the line, and the ringer 15 is connected instead across the line when the switch-hook is down; but when the switchhook goes up, the ringer is disconnected from the line and the transmitter 12 bridged across the line, completing a circuit between the two line conductors 3 and 4. Furthermore, the switch-hook controls the so-called release springs 16, 17 and 18, which springs are adapted to be pressed into contact by the switch-hook arm 19 when the switchhook descends, but which springs are permitted to disengage again as the switch-hook reaches the lower limit of its stroke. However, when the switch-hook rises the said release springs 16, 17 and 18 do not come into contact. The induction-coil 14 is, of course, provided with the secondary winding 20 which, as shown, is connected ina closed local circuit with a receiver 21.

The selector C comprises the well-known vertical line relay 22 and the Yrotary line relay 23, which relays are normally connected with the line conductors, the vertical line relay 22 with the vertical line conducto-r 3, and the rotary line relay 23 with the rotary line conductor 4. The said relays are,

however, disconnected from the line conductors when the side switch of the selector passes to third position. The side switch comprises the vertical side switch wiper 24 to which the vertical line conductor 3 is connected, the rotary side switch wiper 25 to which the rotary line conductor 4 is connected, the private side switch wiper 26 which, upon passing to third position, provides guarding potential for a seized line, and the rotary magnet side switch wiper 27 which, when in second position, closes an energizing circuit for the rotary magnet 28. The side switch is, of course, controlled by the private magnet 29, which private magnet is in turn controlled by the rotary line relay 23. The said rotary magnet 28 is, of course, used for rotating the switch-shaft (not shown) which carries the line wipers 30 and 31 and the private wiper 32. The rotation of the shaft does not, however, occur until the shaft is first raised, and the raising of the shaft is accomplished through the medium of the vertical magnet 33, which magnet is controlled by the vertical line relay 22. After the switch has been operated it may be released by energizing the release magnet 34, which release magnet may be energized while the side switch is in first or second position, if the line relays 22 and 23 are energized simultaneously. Alfter the side switch passes to third position, however,

The selector Yis provided with the well-` known bridgecutoif relayV 36, which is adapted to energize whenever any calling subscriber establishes connection with the line A, whereby the line relays 22 and 23 are disconnected from the battery B and from each other to prevent the switch lfrom being thrown to an off-normal position by theringing current. In addition to said relays I provide, for the operation of the meter H, the vertical and rotary line meter-relays 37 and 38, the relay 37 being inserted between the vertical line wiper 30 and the third pos'- tion contact point 39l of the side switch wiper 24, and being shunted by a condenser 40. The rotary line meter-relay 38 is, in a similar manner, inserted between` the rotary line wiper 31 and the third contact point 41 of the side switch wiper 25, and is also shunted by a condenser 42. There is also provided a meter magnet 43, the energizing circuit-of which is controlled by the meter line relays 37 and 38, and also by a meter magnet relay 44. As shown in the said selector patent, the bridge-cut-o relay 36 Vhas one terminal connected to an off-normal spring 45, which spring is, when the switch-l shaft is in normal position, maintained in engagement with a spring 46 that forms the terminal of the private normal conductor 47, and which is maintained in normal engagement with the spring 45 by the normal 'post arm 48 mounted on the switch-shaft. In addition to the said springs there are other offnormal springs which belong to the same group and which are also controlled by the normal post arm 48, the office of which springs Awill be disclosed hereinafter.

The connector switch D is,y as stated, a modied form of the one shownin the saidV connector patent, and is'provided with the usual line relays 49 and 50. Said relays are provided in order that the subscriber may operate the vertical magnet Y51 that operates the connector switch-shaft (not shown) in a vertical direction, which shaft carries the line wipers 52 and 53 andthe private wiper 54. Through the mediumof the said relays the rotary magnet 55 may be operated, as well as the private magnet 56l and the release magnet 57. As usual, the private magnet 56 Y controls the connector side switch, which side switch'comprises the side switch wipers 58', 592,60 and 61. 1n the said connector there is provided a differential relay 58 having two windings 59 and 60, the winding 59 being inserted between the vertical line relay 49 and the non-grounded terminal of battery B, and the winding 60 being inserted between the rotary line relay 50 and the terminal 7 8 that normally connects with the non-grounded terminal of battery B. Said terminal that normally connects with the non-grounded terminal of battery B in this connector is adapted to be switched from the said non-grounded terminal to the grounded terminal of the battery, whereby the said battery is bridged across the line for supplying talking battery current to the calling subscriber. This switching operation is done by the so-called back-bridge relay 6l (which is provided with two windings 62 and 63), whenever connection is established with the called subscriber. When the called subscriber removes his receiver and bridges his transmitter across his line conductors 64 and 65, the said relay G1 energizes, whereby the shifting or pole-changing operation above described is accomplished. It will be understood, of course, that the called subscriber is at once provided with talking battery current, because as soon as the established connection 4is made one of the windings of said relay 61 is connected to the grounded terminal of the battery and to one side of the main line, and the other is connected tothe non-grounded terminal of the battery and the other side of the main line, thus locating the battery B between the branches of the main line and supplying electrical potential thereto for the purposes set forth. vris soon as the said pole-changing operation is accomplished for supplying the calling subscriber with talking battery c urrent, the meter line relays 37 and 38 being in series in the main line become energized and thereby operate the meter H by energizing the meter magnet 43, which magnet in turn energizes the meter magnet relay 44, the relay 44 in turn energizing and locking itself, and at the same time breaking the circuit for the meter magnet 43, whereby the meter magnet 43 is denergized, which meter magnet 43 in turn breaks the energizing circuit for the meter magnet 44, whereby during conversation only the meter magnet relays 37 and 3S at the selector C remain energized.

The mechanical operations and circuits for thus accomplishing the above results will be described more ininutely in the following: Assuming that the calling subscriber :#:500 wishes to call the subscriber A', the number of whom it will be assumedl is 211; the calling subscriber operates his dial rst for the digit 2, then for the digit l, and again for the last digit 1. Upon operating the dial for the first digit the vertical line conductor 3 is grounded twice and the rotary line conductor 4 is grounded once. Grounding the vertical line conductor 3 twice energizes the vertical line relay 22 twice by establishing a circuit each time from the substation ground G to the ground post 10, thence through the Vertical impulse spring 8 to the vertical line conductor 3, and through the side switch wiper 24 and first-position contact point 66 to the vertical line relay 22, thence through the bridge-cut-oif relay springs 67 and 68 to the battery lead 69, and through battery B to ground G. rl`he vertical line relay 22 then operates as usual to energize the vertical magnet 33, which magnet in turn operates to raise the switch-shaft, in this case, two steps, carrying the shaft wipers 30, 31 and 32 opposite the first terminal of the second level of their banks. It will be understood, of course, that the line wipers 30 and 3l are allotted to the line bank from which trunk conductors lead to connector switches, and that the private wiper 32 is allotted to the private bank from which third or trunkrelease conductors lead to the corresponding connector switches. The grounding of the rotary line conductor 4, which follows the ground impulses to the vertical line conductor 3, as explained, energizes the rotary line relay 23 of the selector C, the circuit for energizing which extends from substation ground Gr to the ground post 10, thence to therotary impulse spring 9, rotary line conductor 4, side switch wiper 25, irst-posi tion contact point 70 to the rotary line relay 23, thence through the bridge-cut-ofl relay springs 7l, 67 and 68 to the battery lead 69, thence through battery B and to ground G. The rotary line relay 23 in turn operates to energize the private magnet 29, which in turn .operates to release the side switch from first to second position, whereby the energizing circuit for the rotary magnet 28 is set up for automatically rotating the switchshaft, which rotation comes to an end as soon as the first idle trunk line is found, at which instant the side switch passes to third position. At the end of the operation for the first digit 2, with the result above explained, the subscriber operates his dial for the second digit, grounding the vertical line conductor 3 once and the rotary line conductor 4 once, whereby the vertical line relay 49 of the. connector D is energized once and the rotary line relay 50 of said connector is energized once. The circuit for the vertical line relay 49 extends from the substation ground G to the vertical line conductor 3, to the side switch wiper 24 (which is now in third position), to the third-position contact 39, thence through the vertical meter magnet relay 37 to the vertical line wiper 30, thence to the vertical trunk conductor 72 to the vertical line relay 49, and through said relay and the winding 59 of the differential relay 58 to the battery lead 69, thence through battery B to ground G. The vertical line relay, upon energizing once, carries the line relay springs the vertical magnet 51 for raising the switch- Yso shaft one step. The spring 74 being grounded the current iiows from the said spring t0 the spring 73, thence through the private springs 75 and 76 to the side switch wiper 61, thence to the first-position contact point 76, vertical magnet 5l to the battery lead 69, thence through battery B to ground G. The shaft and shaft wipers are thus raised one step. The grounding of the rotary line conductor 4 energizes the rotary line relay 50, the energizing current for which Hows from ground Gr to the rotary line conductor 4, thence to the side switch wiper 25, third-positiony contact point 4l, through the rotary meter relay 38 to the rotary side switch wiper 31, rotary trunk conductor 77 to the rotaryy line relay 50,A thence through the winding 60 of the differential relay 58, and through the back-bridge relay springs 78 and 7 9 to the battery lead 69, thence through battery B to ground Gr.V Upon energizing, the rotary line relay 50 carries the spring 80 onto the ground spring 74, thus energizing the private magnet 56 from ground spring 74 to the spring 80, thence through the private magnet 56, and through the back-bridge relay springs 78 and 79 to battery lead 69, thence through battery B to ground G.

, The private magnet operates to trip the side switch from first to second position, at which time the side switch wiper 61 passes onto the second-position contact point 81, to which contact the rotary magnet-55 is connected, whereby, when the vertical line relay 49 operates in response to the neXt digit of the called number, the rotary magnet 55 is energized instead of the vertical magnet 51. At the same time the private side switch wiper G0 engages the second contact point 82, thereby placing the private switch-shaft wiper 54 in connection with the private magnet spring 83, and whereby, if the desired line is busy, a guarding potential for protecting the busy line is extended tothe private magnet spring 83. Ifrthe desired line is busy such guardingspotential is eX- tended to theV private magnet spring 83 when the private switch-shaft wiper 54 is carried onto the busy contact point, whereby, when the private magnet 56 is energized by the last rotary impulse, the private spring 83 is carried onto the private spring 84, which latter is connected with the release magnet 57 and the said release magnet is energized and the connector switch released. After the side switch has passed into second position, as explained, the subscriber operates his dial for the last digit, grounding the vertical line yconductor 3 once and the rotary line conductor 4 for the last time. Grounding the vertical line conductor 3 once causes the vertical line relay 49 of the connector D to be energized over the same circuit which was previously pointed out. The said relay in turn operates to carry the line relay spring 73 onto the ground spring 74, whereby the rotary magnet 55 is energized and the switch-shaft and shaft wipers 52, 53 and 54 are rotated onto the line of the desired subscriber; then when the ground impulse is sent to the rotary line conductor 4 the rotary line relay 50 of the connector D again energizes over circuits that are already known, and again operates the private magnet 56 as above. If the desired line is busy, as already stated, the connector will be released in a manner to be more fully pointed out hereinafter; but if the line is not busy, then as soon as the private magnet 56 denergizes, the side switch passes to third position, at .which timev the side switch wiper 58 engages the third-position contact pointv 85, and the side switch wiper 59 engages the third-position contacty point 86. The side switch wiper r58 extends the trunk conductor 72 through kcontact point 89, puts the private wiper 54 in connection with the grounded terminal of battery B for establishing a guarding potential over the called line, which ground connection at the same time sets up a flow of current through the bridge-cutoff relay of the selector Cof the called line for disconnecting the line relays 91 and 92 from battery B and from each other. It will be noticed that one terminal of therwinding 63 of theback-bridge relay 6l is connected to the private side switch wiper 60', and that as soon as the side switch passes to third position, as explained, the said terminal of the winding 63 is connected to ground. Since the other winding 62 of the said back-bridge relay 61 is, as previously stated, connected .with the non-grounded terminal of battery B, andA since the remaining terminal lof the coil 63 is connected to the rotary side of the main line, and the remaining terminal of the winding 62 is connected with the vertical side of the line, on the called subscribers side ofthe condensers, theY battery B is, therefore, bridged across the called subscribers side of the main line; and as a result, when the said subscriber answers, after being signaled, he energizes the said back-bridge relay 61, said relay being designed and adapted to energize when a circuit is` closed in which the said windings 62 and 63 are putin series with the-battery The mannerin which the called subscriber is signaled will now be explained. Heretofore, it will be remembered, the differential relay 58 has received current through either of the windings 59 or 60 when either of the line relays 49 or 50 has been energized. The said differential relay 58 is consequently energized each time, but it has played no useful part heretofore. The said differential relay 58, however, now plays a Very important part when the calling subscriber signals the called subscriber. The connection having been established the calling subscriber presses his signaling button 93, which button then shifts the spring 94 from the contact point 95 and onto the contact point 9G. Said contact point 90 being connected with the substation ground Gr at the time, the pressing ofthe signaling button 93 operates to ground the vertical line conductor 3. AThe circuit to said conductor is established from ground G to the contact point 96, thence through the spring 94 and through the springs 97 and 98 to the vertical line conductor 3. As a result the vertical line relay 49 of the connector D is energized, and the differential relay 58 is energized. The vertical line relay, upon pressing the line relay spring 7 3 onto the ground spring 74, grounds one terminal of the ringer relay 99 through the side switch wiper 61 and through the third-position contact point 100 of said side switch wiper. At the same time the differential relay 58 operates to connect the other terminal of said ringer relay 99 with the non-grounded terminal of battery B, it being evident that normally both terminals of said ringer relay 99 are disconnected from battery B. The differential relay 58 operates to establish the said connection with the non-grounded terminal of battery B, by pressing the differential relay springsA 101 and 102 in contact. The flow of current is, of course, then set up from the line relay ground spring 7 4 to the line relay spring 73, thence through said side switch wiper G1 to the ringer relay 99, through said relay, and by way of the differential relay springs 101 and 102 to the battery lead 69, thence through battery B to ground G. The ringer relay 99 then operates to bridge the ringer generator E across the line of the called subscriber, at the same time disconnecting the called subscribers line from the calling subscribers line. This operation is attained through the medium of the springs allotted to the said relay 99'. Now when the called subscriber answers, as already explained in the preceding, the back-bridge relay 61 energizes, which relay G1 then operates to shift the spring 78 from the spring 79 and into en gagement with the spring 103. The shifting of the said spring 78 has the effect of transfer-ring one terminal of the winding 60 of the relay 58 from the non-grounded battery spring 79 to the grounded battery spring 103. As a result the battery B is inserted in series with the windings 59 and 60 of the diiferential relay andthe line relays 49 and 50, and is bridged across the main line on the calling subscribers side of the condensers 87 and 88, whereby the calling subscriber is supplied with talking battery current. The flow of current through the line relays 49 and of the connector D is strong enough to energize said relays and carry the trunkrelease springs 115 and 116 into enga gement; and ordinarily the release magnet 57 would be energized, but since theother terminal of said release magnet is normally disconnected from the battery B the engagement of said trunk-release springs 115 and 11G causes no improper operation. The difierential relay 58, however, does not operate, since the windings are arranged to prevent the relay from energizing when they are in series. 1t will be evident that the flow of current is from the grounded terminal of battery B to the third-position contact point 89 of the connector private side switch wiper thence to the `back-bridge relay spring 103, to the spring 78, to the winding 60 of the differential relay 58, through the rotary line relay 50 to the rotary trunk conductor 77, thence through the meter rotary line re lay 38 to the rotary line conductor 4, and through the transmitter 12 of the calling substation to the Vertical line conductor 3, thence through the winding of the Vertical line meter relay 37 to the vertical trunk conductor 72, and through the Vertical line relay 49 and winding 59 of the dilferential re lay 58 to the battery lead 69, thence through battery B to the grounded terminal Gr. This current not only charges the transmitter of the calling subscriber, but at the same time energizes the meter line relays 37 and 38 simultaneously, at which time the springs 104 and 105, controlled by said relays, are brought into contact and a circuit closed through the meter magnet 43 and across the main line from the conductor 100 to the spring 104, thence throng-h the spring 105 to the magnet 43, and through the olf-normal springs 107 and 108 to the conductor 109 on the rotary side of the line.

A portion of the current is, of course1 shunted from the main line by the coil 43, which energizes the said magnet 43. The magnet 43 in turn operates the meter H, causing it to register. At the same time the said magnet 43 presses the springs 110 and 111 into contact, closing a local circuit through the meter relay 44. Said relay then attracts its armature 112, which armature is provided on its lower'end with a member 113 that normally rests over a lug 114 of the spring 108, whereby the spring 108 is normally maintained in engagement with the spring 107. As soon as the armature 112 is Y springs 108 and 107 remain apart. It will be evident that if the called subscriber were to hang up his receiver before the calling subscriber is through talking to him, the' talking battery current will then be cut off from the calling subscribers line, and the meter line relays 37 and 38 will denergize. Then if the called subscriber is again signaled without making a new connection, when the called subscriber returns to the telephone and throws his transmitter across his line again, battery current will now be thrown out to the calling subscribers line, and the meter line relays 37 and 38 will again energize. This, however, will not operate to cause the meter H to again register, since the circuit is still broken at thepoint between the off-normal'springs 107 and 108. However, when the calling subscriber releases, the apparatus is restored to normal condition and themeter H is in position to register.

The restoration of the apparatus is as follows: When the switch-hook 11 descends, the release springs 16, 17 and 18 are brought into Contact, the release spring 16 being grounded. The springs 17 and 18 being connected to the line conductors 4 and 3, the said conductors are grounded simultaneously, and the line relays 49 and 50 and the differential relay 58 of the connector D are energizedsimultaneously in the following manner: The line relay 49, which is energized during talking, does not denergize when ground appears at the vertical .line-conductor 3, but

on the contrary is retained energized. With the rotary line relay 50, however, it is different. Grounding the rotary line conductor 4 shunts or short-circuits the said rotary line relay in series with the winding 60 of the dii'erential relay 58, with the result that the diii'erential relay 58 becomes unbalanced and energizes.

the said energizing circuit for the rotary line relay` 50. This circuit being restablished,

the rotary line relay 50 will energize and the differential relay 58 is further strengthened by the assistance of theV current in the windvlng 60, which current nowflows in a proper As a4 result the differentialv yrelaysprings 102 and 119 are separated, and

direction to assist the current in the wind-V ing 59. The line relays 49 and 50, acting at the same time, carry into contactthe trunkrelease springs 115 and 116, thus placing the release magnet 57 in' direct connection with the third or trunk-release conductor 117 that leads to the selector C. Said trunk conductor is connected to ground at the selector l private side switch wiper 26, which wiper is in third position and in engagement with the third-position grounded contact point 118, through the back-release relay 35. The other terminal of the release magnet 57 is carried into engagement with the non-grounded terminal of battery B by the diilerential relay f 58 which, upon energizing, as previously explained, carries the springs 101 and 102 into contact; and as a result, when the release magnet 57 energizes, the connector switch D is released and at the same time, since the back-release relay 35 energizes in series with the release magnet 57, said release relay 35 in turn closes an energizing circuit through the release magnet 34, which circuit is broken assoon asv the substation release springsfseparate, at which time the switch-shaft and side switch return to normal position.

When the switch-shaft falls, the normal post arm 48 of the selector C strikes the spring 46, carrying said spring into normal engagement with the spring 45 and restoring the springs 108 -and 107, atV which time the armature 112 of the relay 44 is permitted to return to normal position, through the action of a retracting springnot shown, thusY restoring the circuit for the meter magnet 43 to normal condition. scribers line is busy, then when the last rotary impulse comes in, as previously stated,

the private magnet 56 energizes, carryingA ,the switches by again hanging up hisV receiver, at which time the line relays 49 and 50 of the connector D and the differential relay 58 energize simultaneously, as previously explained. The meter H does not, however, register, because although the meter line relays 37 and 38 energize simulta- Tf the called sub-` soi neously when the line conductors 3 and 4 are grounded simultaneously, yet there is no difference in potential between the conductor 106 on the vertical side and the conductor 109 on the rotary side, to which conductors the meter magnet 43 is attached, which difference in potential is absolutely necessary for operating said magnet.

As shown in Fig. 2, the meter H may, if desired, be put under the control of the relay 44, in which case the magnet 43 would control only the springs 110 and 111. The results would be the same as previously explained, except that the meter I-I will, in

that case, register when the magnet 44 energizes instead of when the magnet 43 energizes.

From the foregoing it will be seen that I provide a call-registering device or meter which is responsive to the called subscriber, and that means are provided for enabling the called subscriber to operate the call-registering device or meter when hetakes down his receiver to answer the call. It will also be seen that I provide a call-registering device or meter which is operated by current from a common battery or centralized source of talking current, in combination with automatic switches operated by current from the same source. Vith this arrangement the called subscriber collects the toll, and the calling subscribers never pay tollunless the called subscribers answer.

An important feature of my invention is the use of but a single pair of relay windings in the selector or other individual switch for feeding talking current to the calling telephone line. By this I mean that there are no other coils in the said selector or individual switch through which the battery current flows to the calling line. Furthermore, and as another-feature of special improvement, it will be seen that my improved CalLregiStering device has a bridged electromagnet or relay which is energized by the act of the called subscriber in taking down his telephone, and which causes the actuation of the call-registering mechanism. This is true, of course, of either Fig. 1 or Fig. 2 of the drawings, for in each case an electromagnet is bridged across the calling subscribers line, the bridge being normally open. In Fig. 1 the bridged electromagnet is the ratchet-actuating magnet 43, but as it is provided with circuit-controlling contacts it may also be regarded as a relay. In Fig. 2 the bridged electromagnet is the relay 43, which controls the circuit of the actuating magnet 44. In either case, therefore, it is the magnet 43 which is bridged, b ut in the two different forms of my invention it will be seen that the functions of this magnet are slightly different. Thus for each callregistering device there is an electromagnet or relay which is energized in series with the calling line, another electromagnet which is energized in bridge of and in series with the trunk line, and another electromagnet which is energized over a purely local or auxiliary circuit, and not over any portion of the tall;- ing circuit.

Vhat I claim as my invention is 1. In a telephone exchange system, the combination of a calling telephone line, a called telephone line, connections from the calling line to the called line, including an automatic switch, a callregistering device allotted lto the calling line, responsive to the called subscriber, provided with an electro-magnet associated with said switch, at the central station, bridged across the calling line, and means including the called telephone line for operating said device to register the successful call through said switch.

2. In a telephone exchange system, the

combinationv of calling and called telephone lines, connections from the calling line to the called line, means at a central oiiice for registering the call as soon as the called subscriber answers, provided with a normally open bridge across the calling line, and means including said called telephone line and bridge for controlling the registering operations of said means.

3. In a telephone exchange system, the combination of connectors for making the final connections with called telephone lines, automatic means lfor trunking calling telephone lines into connection with said connectors, call-registering devices allotted to the different telephone lines for registering the calls as soon as the called subscribers answer, each call-registering device provided with a normally open bridge across its allotted line, and means by which the called subscribers close said bridges andI cause said devices to register the calls.

4.` In a telephone exchange system, the combination of telephone lines, automatic means for connecting calling lines with called lines, call-registering devices allotted to the different telephone lines, responsive to the called subscribers lfor the registration of calls, means including the called telephone lines for controlling the said devices and causing the same to register all successful calls, each call-registering device provided with a normally open ,resistance bridge across its allotted line, and means under the control of the called line for closing said bridge.

5. In a telephone exchange system, the combination of telephone lines, call-registering devices allotted to the different lines, responsive to the called subscribers for the registration of calls, common battery means for operating said devices' and supplying talking current to the telephone lines, and means by which closure of any called line operates the registering device of the calling line to register the call, each registering device provided with but a single pair of relayvwindings for feeding talking current to the calling line.

6. A measured-service telephone exchange system comprising a calling telephone line, a common battery, a single pair of relays through the windings of which talking current is supplied from the said battery to the calling subscribers line, a call-registering device controlled byk said relays, a called telephone line, and means by which the called subscriber initiates the energization of said relays to register the call, said relays being individual t0 line.

7. A measured-service telephone exchange system comprising a calling telephone line, an automatic switch individual to said calling telephone line, a centralized source of talking current, a single pair of relays allotted Vto said switch and through the windings of which talking current is supplied to the calling telephone line, a callregistering device controlled by said relays, a called telephone line, and means by which the called subscriber initiates the energization of said relays to register the call. v

8. A measured-service telephone exchange system comprising a calling telephone line, a normally open central station bridge individual to said line, a call-registering device associated With said bridge, a called telephone line, and means by which the called subscriber closes said bridge to A l, actuate the said registering device.

9.In a telephone exchange system, the combination of a calling telephone line, a called telephone line, connections from the calling line to the called line, including an automatic switch, a common battery or centralized source of talking current, a callregistering device allotted to the calling line, a hook-switch for the called line, means responsive to the actionv of said hookswitch for admitting t, lking current to the 45' callingline, and means including a bridged relay, individual to the calling line associated with said switch and in bridge of the talking circuit, said relay responsive to said ,l hook-switch for causing the said registering device to register the successful call through said switch.

10. A measured-service telephone exchange system comprising calling and called telephone lines, an automatic connector intermediate the two lines, relays for said connector, a common battery for supplying talking current through the windings of said relays to the calling telephone line, an individual switch for the calling telephone line, a pair of relays'for said individual switch, andl a call-registering devicecontrolled by therelays of the individual switch, the windings of the relays of the connector and the individual switch being connected in series the calling telephonev with the commonb'attery the calling tel- -said switch and a relay individual to the calling line in bridge of the talking circuit by which the called subscriber causes said device to register the call, and a trunk-line energizing circuit for said bridged relay.

12. In a telephone exchange system, the combination of a calling telephone line, a called telephone line, a'call-registering apparatus allotted to the calling line vbut responsive to the called subscriber, a talking circuit including the two lines, and three energizing circuits for Vsaid call-registering apparatus, one circuit including both sides of the calling telephone line, another circuit including both sides of an intermediate portion of the talking circuit, and the other circuit being purely local or auxiliary to the talking circuit and excluding all portions thereof.

13. In a telephone exchange system, the combination of a calling telephone line, a called telephone line, means having vertical and rotary motion to extend connection from the calling liner to the called line, a call-registering device allotted to the calling line, responsive to the called subscriber, provided with an electromagnet bridged across the calling line at the central terminal thereof, and means including the called' telephone line for operating said device to register tho call.

14. In ,a telephone exchange system, the combination of calling and called telephone lines, means having vertical and rotary motion to extend connection from the calling line to the called line, means for registering the call as soon as the called subscriber answers, provided with a normally open bridge across the calling line at the central terminal thereof, and means including said called telephone line and bridge for'controlling the registering operations of said means.

15. In a telephone exchange system, the combination of connectors having vertical and rotary motion for making the final connections with called telephone lines, automatic means for trunking calling telephone lines into connection with said connectors, call-registering devices allotted to the different telephone lines for registering the calls as soon as the called'subscribers answer,each call-registering device provided with a normally open bridge across its allotted line, and means by which the called subscribers incassa close said bridges and cause said devices to register the calls.

16. ln a telephone exchange system, the combination of telephone lines, automatic means having vertical and rotary motion for connecting calling lines with called lines,

call-registering devices allotted to the liderent telephone lines, responsiv'e to the called subscribers for the registration of calls, and means including the called telephone lines for controlling the said devices and causing the same to register all successful calls, each call-'registering device provided with a normally open1 resistance-bridge across its allotted line at the switch terminal thereof.

17. ln a telephone exchange system, the combination of telephone lines, means having vertical and rotary motion for trunking calling lines into connection with the called lines, call-registering devices allotted to the different lines, responsive to the called subscribers for the registration of calls, common battery means for operating said devices and supplying talking current to the telephone lines, and means by which closure of any called line operates the registering device of the calling line to register the call, each registering device provided with but a single pair of relay windings for feeding talking current to the calling line.

18. A calling subscribers normally open individual bridge controlled by the called subscriber at the central station, automatic switches having vertical and rotary motion for extending connection from the calling line in the direction of the called subscriber, and a registering device operated upon the closing of said bridge.

19. A measured service telephone exchange system comprising a calling telephone line, automatic switches having vertical androtary motion for extending connection from the calling line in the direction of the called subscriber, a common battery, a pair of relays through the windings of which talking current is supplied from the said battery to the calling subscribers line, a call-registering device controlled by said relays, a called telephone line, and means by which the calledd subscriber initiates the energization of said relays to register the call, said relays being individual to the calling telephone line.

20. A measured-service telephone exchange system comprising a calling telephone line, automatic switches having vertical and rotary motion for extending connection from the calling line in the direction of the called subscriber, a normally open bridge individual to said line, a call-registering device associated with said bridge, a called telephone line, and means by which the called subscriber closes said bridge to actuate the said registering device.

21. 1n a telephone exchange system, the combination of a calling telephone line, automatic switches having vertical and rotary motion for extending connection from the calling line in the direction of the called subscriber, a called telephone line, a common battery or centralized source of talking current, a call-registering device allotted to the calling line at the switch terminal thereof, a l

hook-switch for the called line, means responsive to the action of said hook-switch for admitting talking current to the calling line, and means including a bridged relay responsive to said hook-switch for causing the said registering device to register the call.

22. A measured-service telephone exchange system comprising calling and called telephone lines, an automatic connector intermediate the two lines, relays for said connector, means in the connector having vertical and rotary motion responsive to said relays to extend the connection to the called line, a common battery for supplying talking current through the windings of said relays te the calling telephone line, an individual switch for the calling telephone line, a pair of line relays for said individual switch, and a call-registering device controlled by the relays of the individual switch, the windings of the relays of the connector and the individual switch being connected in series with the common battery and the calling telephone line.

28. '1n a telephone exchange system, the combination of a calling telephone line, a called telephone line, means including a line wiper having vertical and rotary motion to extend the connection from the calling line in the direction of the called line, a callregistering apparatus allotted to the calling line but responsive to the called subscriber, a talking circuit including the two lines, and three energizing circuits for said call-registering apparatus, one circuit including both sides of the calling telephone line, another circuit including both sides of an intermediate portion of the talking circuit, and the other circuit being purely local or auxiliary to the talking circuit and excluding all portions thereof.

24. ln a telephone system, a ratchet mechanism associated with a bridge individual to and across the calling line at the central station, a register associated with said mechanism, and means in said bridge responsive to the called subscriber, for operating said ratchet mechanism and register, when talking current is received at the calling substation. R

25. 1n a telephone system, an individual trunk-selecting switch forthe calling line, a pair of relays therefor' for controlling a normally open relay bridge for the calling -the closing of said bridge.

26. In atelephone exchange systen'n-the f combination ofcalling and called telephone lines, connections from the calling line to the called line, a pair of relays adapted to Vbe included in series in this connection, and

a call-registering device adapted to be operated by said relays.

27. In an automatic telephone exchange system, the combination of calling and called lines, automatic switches for extending connection from the calling to the called line, a pair of relays adapted to be connected in series in said circuit, and a callregistering device controlled by said relays.

28. In a telephone exchange system, the combination of calling and called telephone lines, connections from the calling line tothe called line, a pair of relays adapted to be included in series in this connection, said relays adapted to be energized upon the response of the called subscriber, and a callregistering device adapted to be operated by Vsaid relays. Y A

n 29. In an automatic telephone exchange system, the combination of calling and called lines, automatic switches for extending connection from the calling to the called line, a

pai-r of relays adapted to be connected in series in said circuit, said relays adapted to be energized upon the Vresponse of the called subscriber, and a call-registering device controlled by said relays.

' 30. A calling subscribers telephone line provided with a normally open bridge individual to and across the calling line, the 'closing of which is controlled by the called subscriber, connections from the calling line to the called line, means for closing said Ybridge as soon as the .called subscriber answers, and a registering device operated upon the closing of said bridge.

31. A calling subscribers telephone line provided with a normally open bridge across the talking' circuit, the closing of which is controlled by the called subscriber, connections from the calling line to the called line, means for closing said bridge as soon as the called subscriber answers, and a registering device fat the central station operated upon the closing of-said bridge.

32. In a telephone exchange system, the combination of calling and called telephone lines, an automatic switch controlled over the calling line, means for registering the call as soon as the called subscriber answers, and means including said called telephone line and a circuit controlling relay indi- "vidual to the calling line but normally disconnected therefrom, for controlling the' registering operations of said means.

33. In a telephone exchange system, the combination of connectors for making the final connections with called telephone lines,

called telephone line, trunklng the calling line into connection automatic means for trunking callingcommon battery telephone lines into connection with said connectors, call-registering devices allotted to the different telephone lines for registering the calls as soon as the called subf scribers answer, and means including a relay individual to the calling line, but normallydisconnected therefrom, by which the called subscriberscause said devices to register the calls.

34C. In a telephone exchange system, the

kcombination of telephone lines, automatic means for connecting calling lines with called lines, including common battery connectors -for finding the called lines, call-registering devices allotted to the different telephone lines, responsive to the called subscribers for the registration of calls, and means including a relay individual to the calling line, but normally disconnected therefrom, for n controlling the said devices and causing the same to register all successful calls.

35. In a telephone exchange system, the

combination of a calling telephone line, a

called telephone line, a common battery or centralized source of talking current, a callregistering device allotted to the calling line, a hook-switch for the called line, means responsive to the action of said hook-switch for admitting talking current to the calling line, means including a relay responsive to said hook-switch for causing the said registering device'to register the call, and means for locking said device'rag'ainst further oper- .ation while the two lines are connected. y

36. In a telephone exchange system, the

Aconnection from a calling to a called subscribers. line, a call-registering device allotted to the calling line, means by which the called subscriber operates said device to register the call, and means for locking the said i device against further operation while the two lines are connected.

38. In a telephone exchange system, the combination of a calling telephone line, a automatic means for with the called line, controlled by the calling subscriber, atrunk-k release circuit, which circuit includes no portion of the talking circuit, a call-registering device allotted to the calling line, and means for disconnecting the two lines and restoring said callregistering device by the closure of said trunk-release circuit.

39. In a telephone system, means including' a double wound relay having one wind* ing connected to each side of the talking circuit by which the called subscriber controls the supply of talking current to the substation of the calling subscriber, and a call-registering device comprising a rotary element and means for actuating the same responsive to the flow of talking current to the calling subscriber.

40. In a telephone system, means by which the called subscriber controls the supply of talking current to the calling subscriber, a relay individual to the calling subscriber and responsive to the flow of talking current, and a call registering device controlled by said relay.

4:1. In a telephone system, a circuit-controlling relay individual to the calling subscribers line responsive to the called subscriber, a call-registering device controlled by said relay, and means having one motion to select groups and another motion to connect with the called line in any group selected by the first motion of the same means, both motions controlled over said line from the substation thereof.

4:2. In a telephone system, a relay individual to the calling subscriber, a call registering device controlled by said relay, means by which the called subscriber energizes said relay when he answers, and means having one motion to select groups and another motion to connect with the called line in any group selected by the first motion of the same means, both motions controlled over said line from the substation thereof.

43. In a telephone system, means by which the called subscriber controls thev supply of talking current to the calling subscriber, ya relay individual to the calling subscriber and responsive to the fiow of talking current, a call registering device controlled by said relay, and means having one motion to select groups and another motion to connect with the called line in any group selected by the first motion of the same means, both motions controlled over said line from the substation thereof.

4A. In a telephone system, a subscribers line, a service meter' provided with an operating magnet associated with said line, an automatic trunkrselecting switch for eX- tcnding connection from said line, a pair of Copies of this patent may be obtained for five cents each, by addressing relays individual to the line and an energizing circuit for said operating magnet controlled by said automatic switch and said relays.

45. In a telephone system, a plurality of subscribers lines, means including an automatic switch for establishing connection between two of said lines, a service meter associated with the calling line, an operating magnet for said meter provided with an energizing circuit having a normally open contact controlled by said automatic switch, a relay individual to the line controlling a second normally open contact in said circuit, means for closing said rst normally open contact when said switch has been operated,

' and means for operating said relay to control the second normally open contact upon the response of the called subscriber.

' a6. In a telephone system, a plurality of subscribers lines, means including an automatic switch for establishing connection between two of said lines, a service meter associated with the calling line, an operating magnet for said meter provided with an energizing circuit having a normally open contact controlled by said automatic switch, a relay individual to the line included in the line circuit for controlling a second normally open contact in said circuit, means for closing said first normally open contact when said switch has been operated, and means for operating said relay to control the second normally open contact upon the response of the called subscriber.

47. In a telephone system, a plurality of subscribers lines, means including automatic selecting and connecting switches for establishing connection between two of said lines, a service meter associated with the calling line, an operating magnet therefor provided with an energizing circuit having a normally open contact controlled by one of said selecting switches, a relay included in the line circuit and individual to the line for controlling a second normally open contact in said circuit, means for closing said first normally open contact when said switch has been operated, and means in said connector for operating said relay to control the second normally open contact upon the response of the called subscriber.

Signed by me at Chicago, Cook county, Illinois, this 4th dayof December, 1906.

ED'VVARD D. FALES.

"Witnesses:

ARTHUR B. Srnnur, I-Ianmn'rr M. MERRIAM.

the Commissioner kof Ratents,

Washington, D. C. 

